/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.crazymaker.servlet.container.netty.resource;

import com.crazymaker.servlet.container.netty.utils.ConcurrentDateFormat;

import java.io.InputStream;
import java.util.Date;

public abstract class AbstractResource implements WebResource
{

    private final WebResourceRoot root;
    private final String webAppPath;

    private String mimeType = null;
    private volatile String weakETag;


    protected AbstractResource(WebResourceRoot root, String webAppPath)
    {
        this.root = root;
        this.webAppPath = webAppPath;
    }


    @Override
    public final WebResourceRoot getWebResourceRoot()
    {
        return root;
    }


    @Override
    public final String getWebappPath()
    {
        return webAppPath;
    }


    @Override
    public final String getLastModifiedHttp()
    {
        return ConcurrentDateFormat.formatRfc1123(new Date(getLastModified()));
    }

    @Override
    public final String getETag()
    {
        if (weakETag == null)
        {
            synchronized (this)
            {
                if (weakETag == null)
                {
                    long contentLength = getContentLength();
                    long lastModified = getLastModified();
                    if ((contentLength >= 0) || (lastModified >= 0))
                    {
                        weakETag = "W/\"" + contentLength + "-" +
                                lastModified + "\"";
                    }
                }
            }
        }
        return weakETag;
    }

    @Override
    public final void setMimeType(String mimeType)
    {
        this.mimeType = mimeType;
    }


    @Override
    public final String getMimeType()
    {
        return mimeType;
    }


    @Override
    public final InputStream getInputStream()
    {
        InputStream is = doGetInputStream();

        if (is == null || !root.getTrackLockedFiles())
        {
            return is;
        }

        return new TrackedInputStream(root, getName(), is);
    }

    protected abstract InputStream doGetInputStream();


}
